Rotations

[Valerie Sutton]

SignWriting List
June 5, 2004

Hello Daniel, Bart, Steven and everyone -
Thanks for the messages on this...and also your thoughtful care for 
detail....Just want you to know that I will dive into this discussion 
in about two hours...Lots to tell you...and we will resolve this so 
that no one feels confused...users or programmers!

Val ;-)

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On Jun 5, 2004, at 2:10 AM, Daniel Noelpp wrote:

> Hello Valerie, hello Bart and Steven, hello SignWriting list!
>
> Bart Braem wrote:
>
>> One other thing we would like to ask: please make all symbols turn in
>> the same direction, so all counter-clockwise for example. Currently 
>> some
>> symbols do turn the other way round and that's pretty irritating when
>> programming: if you want to display a mirrored or rotated symbol you
>> always need to check the category. When you just specify one rotation
>> programmers can always be confident that when the format reads
>> "turn 45 degrees" it will always be the same direction.
>
> I am not sure that I understand you. Are you telling, that there were 
> some "weird" symbols rotating the other way round? I didn't find any 
> symbols in any category rotating differently than the other symbols in 
> the same category except for symmetry. My brother did a lot of detail 
> work when we configured the symbolset together. So I have to ask him 
> whether he discovered something strange that I might have overlooked.
>
> Perhaps we are talking about different things:
>
> 1. About the ordering of rotations whithin the Sign Symbol Sequence, or
> 2. the rotation code within the files or
> 3. the exact behaviour of the rotation key?
>
> I don't know. I am going to try explain my view about point 3 and what 
> I have discovered so far. Let's start with an example: the Index 
> Finger of both hands pointing forward and then both hands turned 45 
> degrees outward:
>
> <rotation.PNG>
>
> If you do the Index Finger together with both hands, both symbols are 
> a mirror of each other. If you turn the left hand about 45 degrees to 
> the left then you have to turn the right hand the same amount to the 
> right so they still are a mirror of each other. That's why the mirror 
> was turned in the other direction and this is very natural.
>
> The problem I see with this approach: It is not immediately evident or 
> very visually clear that something is "righthanded" or "lefthanded". 
> It will confuse and even bewilder users when they rotate things. And 
> voilà: Neither SignWriter DOS nor Java rotate depending on mirror. 
> They rotate always counter-clock-wise (and with the Shift-key pressed 
> clock-wise).
>
> In GUI designing there is the principle of the least surprise. An 
> action should contain as few surprises as possible and always work the 
> same as expected. Making rotation dependent on mirror would bring a 
> lot of surprise and suspense.
>
> I have to confess that I still need some thinking about this subject, 
> especially about point 1 and 2. I agree with Steven and Bart that 
> rotations should always have the same direction, but not because the 
> programmers get confused, but because the users could get confused.
>
> In the SymbolBank the mirrors of the hand symbols rotate the other way 
> round. Perhaps it is a good idea to leave it this way? So we have the 
> best of the two different possibilities? The GUI (the rotation key) 
> always rotates the same, but the data knows about the mirror and 
> rotates differently for the mirrors?
>
> Daniel